JPH0129128Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Technical Field> The present invention relates to an air suspension device used as a suspension device for automobiles.

<Prior Art> As a conventional air suspension device of this type, there is one described in, for example, Japanese Utility Model Publication No. 53-41208.

This is constructed as shown in FIG.
By interposing a leveling valve 5 and a three-way valve 6 in one air path 4 leading to the air path, automatic adjustment of the vehicle height by the leveling valve 5 and manual change of the vehicle height can be controlled as desired. There is.

In this way, if automatic adjustment of the vehicle height and change of the vehicle height can be controlled arbitrarily, the vehicle height can be maintained at a predetermined value regardless of the vehicle weight, as in the past.
The vehicle height can be changed as necessary, making it easier to load and unload cargo and get passengers on and off. Furthermore, when applied to an air suspension device for a tractor, there are advantages such as improved workability in connecting trailers of different heights.

However, in the past, only one system of exhaust path was provided, so the speed at which the vehicle height was lowered varied greatly depending on the vehicle weight. In other words, for example, in a truck, the weight of the vehicle changes greatly between when it is loaded and when it is empty, so if the cross-sectional area of the exhaust path or the exhaust resistance is set so that the optimal vehicle height lowering speed is achieved when the vehicle is loaded with a large weight, If the cross-sectional area of the exhaust path or the exhaust resistance is set to take the optimal vehicle height lowering speed when the vehicle is light and empty, the vehicle weight will be lower. There were problems such as the speed at which the vehicle height lowered when the vehicle was loaded, which increased.

<Purpose of the invention> The present invention has been developed in view of the above-mentioned circumstances. The objective is to make it possible to select the descent speed depending on the conditions, for example, to improve the efficiency of trailer coupling work.

<Structure of the invention> In order to achieve such an object, the present invention provides a leveling path that adjusts the air pressure of the air spring according to the vehicle weight to maintain the vehicle height at a predetermined value, and a leveling path that controls the air in the air tank to the air spring. an air supply route that raises the vehicle height by forcibly supplying the air to the air spring, and two exhaust routes that lower the vehicle height by discharging the air from the air spring to the atmosphere, and manual switching to open and close each of the routes. By providing a valve, the speed at which the vehicle height is lowered can be adjusted by selectively using the exhaust route according to usage conditions.

<Example> Examples of the present invention will be described below.

FIG. 2 shows an embodiment of the present invention,
The input side of a leveling valve 12 is connected to an air tank 10 mounted on the vehicle via a three-way joint 11. Additionally, an air spring 13 interposed between the vehicle body frame and the axle (not shown) is connected to the air spring port 14a, and the leveling port 1 of the switching valve 14 is connected to the air spring port 14a.
4b and the output side of the leveling valve 12, and the input side of the leveling valve 12 and the switching valve 14.
is connected to the air supply port 14c via an air supply passage 15.

Then, an exhaust port 14d provided in the switching valve 14
is connected to a signal port of an exhaust valve 16 attached to the air spring 13. 14e is an atmospheric port provided on the switching valve 14, 14f is a control lever of the switching valve 14, and 16a is an atmospheric port provided on the exhaust valve 16.

Note that the switching valve 14 is constituted by, for example, a rotary type switching valve, and the control lever 1
When 4f is shifted to the running position shown, the switching valve 14
The air spring port 14a provided at the top is connected to the leveling port 14b, and when shifted to the stop position, the air spring port 14a is completely disconnected from all ports. Further, when the control lever 14f is shifted to the up position, the air spring port 14a is connected to the air supply port 14c, and when the control lever 14f is shifted to the down position 1, the air spring port 14a is connected to the atmosphere port 14e. Then, when the control lever 14f is lowered and shifted to position 2, the air spring port 14a is separated from all ports, the exhaust port 14d is connected to the air supply port 14c, and signal pressure is applied to the signal port of the exhaust valve 16. supply is becoming available.

In the air suspension device configured as described above, the control lever 14f is normally held at the traveling position shown in FIG. Then, the air spring port 14a of the switching valve 14 is maintained in communication with the leveling port 14b, so that the air pressure supplied to the air spring 13 is automatically adjusted according to the vehicle weight, and the vehicle height is maintained at a predetermined value.

When attempting to raise the vehicle height, the control lever 14f is switched to the raised position. Then, air spring port 14a and leveling port 1
4b is cut off and the air spring port 14a
is connected to the air supply port 14c, so compressed air is forcibly supplied to the air spring 13 regardless of the vehicle weight. For this reason, the air spring 13 expands and the vehicle height increases.

When lowering the vehicle height, the control lever 14f is switched to position 1, for example. Then, air spring port 14a is now connected to atmospheric port 1.
4e, the compressed air of the air spring 13 is discharged into the atmosphere from the atmospheric port 14e of the switching valve 14. As a result, the internal pressure of the air spring 13 decreases, the spring 13 shortens, and the vehicle height decreases.
Further, when the control lever 14f is lowered and switched to position 2, the air spring port 14a is separated from all ports, and at the same time, the air supply port 14c is
is connected to the exhaust port 14d. Then, signal pressure is supplied to the signal port of the exhaust valve 16 provided in the air spring 13, so the exhaust valve 16 opens.
The air from the air spring 13 is sent to the atmospheric port 1 of the exhaust valve 16.
It is discharged from 6a. Therefore, in this case, the air is substantially directly discharged from the air spring 13 into the atmosphere, so that the exhaust resistance is small and the exhaust speed is high. For this purpose, as described above, the control lever 14
Compared to the case where f is lowered and switched to position 1, exhaust is performed more smoothly, so the vehicle height lowers at a higher speed.

In other words, by setting the exhaust route to two systems with different cross-sectional areas or exhaust resistances, and selecting and using the exhaust system according to usage conditions such as vehicle weight, the vehicle height lowering speed can be selected. The lowering speed of the vehicle height can be maintained at a predetermined value by lowering the control lever 14f and switching it to position 1, and when a heavy vehicle is loaded, lowering the control lever 14f to position 2.

Incidentally, when the control lever 14f is switched to the stop position, communication between all ports is mutually cut off, so that the air spring 13 is sealed and the vehicle height does not change.

In the above embodiment, an exhaust valve 16 is attached to the air spring 13, and the exhaust resistance of the exhaust system by the exhaust valve 16 is made smaller than the exhaust resistance of the exhaust system by the atmospheric port 14e of the switching valve 14, thereby lowering the control lever 14f. The vehicle height is lowered at high speed when the switching operation is performed to the position shown in FIG. When the control lever 14f is lowered to position 1, the air is exhausted from one atmospheric port,
When the control lever 14f is lowered and switched to position 2, the vehicle height may be lowered at a lower speed by exhausting air from the two atmospheric ports and relatively changing the cross-sectional area of the exhaust path. or,
In the embodiment, one unitized switching valve 14 is used, and this switching valve is controlled directly by one control lever to avoid complication of the interlocking mechanism due to an increase in the number of parts. However, the specific configuration of the switching valve is arbitrary.

<Effects of the invention> As explained above, according to the invention, the exhaust system from the air spring can be selectively used depending on the usage conditions represented by the vehicle weight, etc. Since the lowering speed of the vehicle height can be selected, the workability of connecting the trailer can be improved.

[Brief explanation of the drawing]

FIG. 1 is a schematic circuit diagram of a conventional example, and FIG. 2 is a schematic circuit diagram of an embodiment of the present invention. 10...Air tank, 12...Leveling valve, 13...Air spring, 14...Switching valve, 14f
...Control lever, 16...Exhaust valve.

Claims (1)

[Scope of utility model registration request] a leveling route that adjusts the air pressure of the air spring according to the vehicle weight to maintain the vehicle height at a predetermined value; and an air supply route that forcibly supplies air from the air tank to the air spring to raise the vehicle height; It is equipped with two exhaust paths for lowering the vehicle height by exhausting the air from the air spring to the atmosphere, and a manual switching valve for opening and closing each of the paths, and the exhaust gas is controlled by operating the switching valve. An air suspension device characterized in that it is configured to adjust the lowering speed of a vehicle height according to usage conditions by selecting and using a route.